Paper manufacture



mateobject which is to produce sized pa .er the Patented Dec. 29, 1931UNITED STATES ,PATENT OFFICE :anwm surmzars'rnn m JOSEPH A. wananu, orwns'rnncox, manna, AfiSIGNOBS -'ro s n. WARREN comm, or nos'ron,mssacrrusnr'rs, a conrom'rrorr or M CH SETTS Ho Application fled April7,

Our invention relatesto the manufacture of sized and filled paper. Weemplo herein the words sized and sizing to efine a treatment of paper inits manufacture which ,5 renders an 0t erwise bibulous paper webrelatively resistant to absorption of liquid,

such as writing ink.

Furthermore our invention has for its object the employment as fillingmaterial for alkaline compounds of alkaline eart metals, of whichcalcium carbonate is an example; and which, if introduced into papermaterial-in the beater with-the usual rosin size, so acts as to defeatthe ultian acceptable filled and sized paper. Heretoforeit has beenfound impracticable to employ any of the said compounds as fillermaterials for sized paper; our invention herein described ischaracterized by the association with such material as calcium carbonateand the other ingredients of a batch of paper of a corrective orprotective material which will enable the paper to be properly filledwith the comgs minuted solid material and at the same time adequatelyand acceptably sized. a Inthe specification which follows, twoexamplesof preparation and manipulation of characteristic'materials are given indetail. Since precipitated calcium carbonate in available to many apermanufacturers that material is sel for the illustrations.

-Exmm No. l

sizing material and pro 85 7 Preparation 0- tect'i've em by weight) Mix1500 parts rosin with-225 arts sodium 40 carbonate in sufficient waterto acilitateagitation and cook this with live steam until all of thecarbon dioxide has'been driven oif. To this add 900 parts melted araflinand, preferably, 100 parts sodium silicate, (the sodium silicate is notindispensable but it has been 1 ;found to assist in the production ofemulsion) Stir the mixture thoroughly and then run it through a colloidmill, or otherwise treat it to produce thorough emulsion of the (partsand proportion;

rum murac'runn 1928. Serial at. 288,367,

Preparation of lime mud (01100,)

Take a wet lime mud containing 200 arts of ()aCO and about the same(plantity o water and add to-this as much- 0 the above de scribedemulsion as will contain 1% (parts 'parafiin and after mixing thoroughlyad also 3.75 parts of alum in water solution. For

alum there may be substituted that quantity of aluminum hydrate as wouldbe produced by converting the 3% parts of alum to hydrate. pebble mill,or otherwise agitate.

In the beater provide a batch containing parts fibre (for instance halfsulfite fibre and half soda fibre) with the usually proportionatequantity of water. To this add an ordinary rosin sizecmulsion inquantity to pro-- vide A part rosin, then add part alum. The foregoingmaterials having been thoroughly worked and mixed in the beater, add thelime mud preparation above described in such quantity as to supply 30parts of (laCO This filler material as prepared should be added in thewet state; if it has been allowed to dry the water-repellentcharacteristic of the UaCO, would render it extremely difiicult to rewetand mix the material in the beater. When-the above described fillermaterial has been duly distributed and mixed the form. f waste lime mudis yimmediamly in' the'beater, add a solution containing 3 parts of alumas convenient before the batch of paper stufi is ready to be run out onthe paper ma 0.

' Exams: No. 2

' Preparation of rosin size and parafi/n emxwlsion as prescribed forExample A o. 1

Start the beater batch as before with 50 parts of fibre and then put ina quantity of wet lime mud equivalent to 30 parts dry CaCO. and at thesame time a sufiicient quantity, of the rosin size and paraflin emulsionto provide one part of parafiin. When these materials have beenthoroughly mixed by the beater action, then add 6 parts alum,insolution, before the batch is run on the paper machine.

The parafiin emulsion in either of the illustrative examples aboverecited forms a pro- Grind this mixture for a time in a y tectivebarrier around or over the otherwise detrimental CaCO particles to suchan extent that they do not react as they otherwise would to prevent theproduction of a properly 5 and truly sized paper. The quantitativeproportions of materials hereinabove given are such as we know to beeffective; these proportions can doubtless be varied and constituentquantities diminished in the interest of 1 economy without defeating themain object.

We claim: a

1. Method of manufacturing filled and sized paper, characterized by theemployment as a filler of an alkaline compound of an alkaline earthmetal in association with emulsified parafiin and rosin as a size.

2. Method of manufacturing filled and sized paper, characterized by theemployment as a filler or calcium carbonate in association withemulsified parafiin and rosin as a size.

3. Method of manufacturing filled and sized paper, characterized by theemployment as a filler of an alkaline compound of an alkaline earthmetal associated with emulsified paraflin and rosin as a size, and theaddition of alum as a final step in the beater.

4. Method of manufacturing filled and sized paper, characterized byemployment as a filler of calcium carbonate in association withemulsified parafin and rosin as a size, and the addition of alum as afinal step in the beater.

5. Sized papercontaining as a filler an alkaline compound of an alkalineearth metal, associated with parafiin and rosin as a size.

6. Sized paper containing as a'filler calcium carbonate, associated withparafiin and rosin as a size.

40 Signed by us at Westbrook, Maine, this fifth clay of April, 1928.

EDWIN SUTERMEISTER. JOSEPH A. WARREN.

